VCS - Synopsys

Datasheet

VCS

Industry’s Highest Performance Simulation Solution

Overview Key Benefits

The Synopsys VCS® functional Industry-leading performance and capacity
verification solution (Figure ``Compile time: Partition compile, Precompiled IP, Dynamic Reconfiguration
1) is the primary verification ``Runtime: Save/Restore, Constraint Solver optimization, Multicore
solution used by most of the
world’s top 20 semiconductor Advanced simulation technologies
companies. VCS provides the ``Native Low Power, X-Propagation, SystemC and AMS Cosimulation,
industry’s highest performance
simulation and constraint Comprehensive planning, coverage and execution management
solver engines. In addition, the native integration
comprehensive VCS solution ``VCS provides key turnaround time and ease-of-use benefits via native integration
offers Native Testbench (NTB)
support, broad SystemVerilog with Verdi® debug, VC Formal and VC VIP
support, verification planning,
coverage analysis and closure, Design VCS Assertions
and native integration with
Verdi, the industry’s de-facto Testbench
debug standard. VCS is uniquely
positioned to meet designers’ Single compiler
and verification engineers’ needs
to address the challenges and Performance Advanced Planning
complexity of today’s SoCs. and capacity simulation and coverage

Profiler X-Prop Verification planner
Partition compile
Native Low Power mCanoavgereamgeent
Precompiled IP
Constraint solver Execution manager

Dynamic reconfig SystemC simulation Adaptive exclusions

Save/restore AMS cosimulation Formaanlaclyosviesrage
assLeortwiopnos/wceorver.
Multicore support Congruency

Native code generator

Figure 1. VCS simulation solution

Language compliance

VCS supports all popular design and verification languages, including SystemVerilog, Verilog, VHDL,
OpenVera™, SystemC™, and the Accellera® UVM™, VMM, and OVM methodologies (Figure 2). VCS’ support
for Accellera UVM also includes access to the VMM/UVM interoperability kit, which enables the use of VMM
with UVM and vice versa. Besides supporting digital circuit design, VCS also supports analog and mixed-
analog designs through Verilog-AMS, SPICE and SPF. This comprehensive support for advanced flows and
methodologies enables VCS to help users develop the highest-quality mixed language functional verification
environments in the shortest amount of time.

Verification Verification
planning management

Coverage Constraint
and analysis solver

Protocol Template
debug generators

Native UVM-aware AMS UVM TLM/SC
UVM VIP debug testbench adaptors

Figure 2. Complete SystemVerilog ecosystem

Verification Continuum Platform

VCS is the center of the most comprehensive and natively-integrated functional verification ecosystem in the
industry. Complementing simulation, the VCS functional verification ecosystem provides formal verification
(VC Formal), emulation (ZeBu), testbench quality analysis (Certitude) and comprehensive coverage closure.
The VCS ecosystem is a core element of the Synopsys Verification Continuum Platform (Figure 3).

Verification Continuum Platform

Planning and coverage
Debug

Virtual Static Simulation Emulation FPGA-based
prototyping
prototyping and formal

VIP, models and databases

Figure 3. Synopsys Verification Continuum Platform

2

Performance

VCS is the industry’s highest performance simulation solution. VCS offers both industry-leading compile time
and run time performance improvement technologies.

Compile time reduction for SoC designs
VCS provides advanced tools for reducing compile turnaround time for complex SoC designs, including
Precompiled IP support targeted at IP integration flows, Partition Compile to isolate portions of the testbench
that are not changing during development cycles, and Dynamic Reconfiguration to compile for a target and
select which model is used at runtime (Figure 4). Combined, these tools offer the most comprehensive set of
solutions to maximize compile efficiency, and reduce turnaround time for SoC verification flows.

Compile for all blocks Run only with the blocks or versions you need
TOP TOP

DUT B1 B2 B3 B4 DUT B1 Blackbox Blackbox AMS
2 3 representation

Figure 4. Dynamic reconfiguration

Partition compile
VCS’ Partition Compile technology allow users to achieve up to 10x faster compile time by only recompiling
code that has changed, and reusing the libraries for the unchanged modules already compiled earlier.

Precompiled IP
VCS’ Precompiled IP flows enables up to 2X compile time improvement in IP integration for SoC flows.
Precompiled IP flows reduce scratch compile time for hierarchical designs, enable integration of IPs with
different debug and coverage capabilities, and allows automatic incremental compile of IPs and clusters.

Dynamic Reconfiguration
VCS’ Dynamic Reconfiguration (Figure 4) feature enables turnaround time reduction over entire regressions by
allowing users to compile once, and run different configurations/testbenches without need for recompiles. All
debug and coverage features work seamlessly regardless of configuration.

Simulation runtime reduction
VCS’ high performance simulation engines are continuously improved with state-of-the-art performance and
memory optimization technologies. These technologies provide best-in-class out of the box performance, and
also support tuning simulator performance to a wide variety of user environments.

Save/Restore
Save/Restore feature (Figure 5) lets the user save the state of simulation in a file for it to be restored at another
time or on a different machine. Designs that have a long design initialization simulation can benefit from this
feature by saving the initial state and restoring the simulation to after initialization in subsequent runs thereby
reducing simulation time.

3

reset test1

reset test2

t reset test3
Long design initialization simulation repeated by each test case

SimState

Save Restore/ Restore/ Productivity gain
reseed reseed

reset test1 test2 test3
t

Figure 5. Save/restore benefit

Constraint Solver

VCS’ industry-leading, high-performance constraint solver technology is powered by multiple solver engines
that simultaneously analyze all user specified constraints to rapidly generate high-quality random stimulus that
verifies corner case behavior. The constraint solver engines will find a solution to user constraints if one exists,
minimizing constraint conflicts and maximizing verification productivity. This feature is essential for directing
the randomized testing strategy towards a meaningful space and speeds up bug finding.

Multicore Support

VCS’ multicore technology offers two robust use models: design-level parallelism (DLP) and application-level
parallelism (ALP) (Figure 6). DLP enables users to concurrently simulate multiple instances of a core, several
partitions of a large design, or a combination of the two. ALP allows users to run testbench, assertions,
coverage, and debugging concurrently on multiple cores. Multicore technology has shown up to 2x runtime
speed ups on GLS designs.

Application level Coverage Design level

Multicore AssertionCore 0 Core 1 Multicore
compiler DebugCore 3 Core 2compiler

Design Multicore Design Multicore
Assertion native code native code
Assertion
Coverage Coverage Core 0 Core 1
Core 3 Core 2
Debug Debug

Figure 6. Verdi design and testbench debug

Advanced Simulation Technologies

Beyond simulation performance, VCS provides the broadest support for advanced simulation technologies
needed to accurately and completely verify today’s advanced designs.

Native Low Power
VCS’ Native Low Power (NLP) simulation technology provides VCS with comprehensive low power verification
and debug capabilities. NLP integration with Verdi also enables easy LP debug with advanced LP features,
and provides excellent support for LP assertions and coverage for coverage-driven verification flows. VCS’
native low power solution allows user to perform multi-voltage simulations so that they can feel the freedom to
implement several techniques for power management.

4

X-Propagation

Certain RTL semantics, such as using x-value to denote indeterminate state, may not model actual hardware
behavior accurately. Instead of having to rely on increasingly costly gate level simulation, VCS provides a
way to simulate x-propagation in multiple modes to model x-value in either more, less or equally optimistic
modelling as compared to the regular gate-level simulation

Conventional RTL simulation masks power-on reset bug RTL simulation with X-Propagation uncovers bug

RST

if ( a ) b if ( a ) b
a b = 0; a b = 0; X
else X else
X b = 1; 1
b = 1;
In simulation, output “b” is 1 when “a” is X Matches hardware behavior

Figure 7. VCS X-propagation support

SystemC simulation and Cosimulation support

VCS SystemC support is fully compliant with IEEE 1666 SystemC versions, and provides both direct
simulation and cosimulation support. Direct variable access from/to SystemVerilog is supported, as are
function calls across languages. VCS Profiler supports native SystemC profiling, and advanced debug is
supported in Verdi CBug feature.

Component Percentage
0.00%
HSIM 10.07% SystemC
0.5% profile data
SystemC 89.88%
89.88%
KERNEL
100.00%
VERILOG Module
Total Table 1. VCS

TOTAL

AMS Cosimulation

VCS provides many benefits for AMS designers namely – real number modeling, native low power and
advanced methodology with AMS testbench. In addition, all analog and mixed signal data can be viewed in
Verdi’s advanced AMS debug environment, which is natively integrated with VCS to enable fastest analysis
and finding root cause.

Planning and Coverage

A verification cycle is dominated by the time meeting coverage goals and spent in debug. VCS is natively
integrated with Verdi Coverage (Figure 8) to support advanced coverage driven verification methodologies.
VCS includes multiple integrated technologies – assertions, assertion checkers, interactive debug and Unified
Report Generator (URG) for coverage data – to help define, measure and report coverage goals, and find
coverage holes. VCS natively supports not only the complete SVA syntax from Verilog LRM, PSL and OVL, but
also provides useful controls to manage the assertion output and performance of simulation. VCS’ regression
execution management capabilities provides powerful configuration, regression results database, and
compute farm management features.

5

Plan Attributes Coverage Coverage
entry Metrics summary detail

Link spec Subplans Source
to plan code

Console

Figure 8. Verdi Verification Planner and Coverage Analyzer windows

Native Integrations

Native integrations between the high performance VCS simulation engine and the other advanced engines
in the Synopsys Verification Continuum Platform (Figure 3) enables improvements in time-to-market by up
to months.

The Verification Continuum Platform’s unified verification architecture eliminates these discontinuities with
VCS Unified Compile, Verdi Unified Debug, and key native integrations such as the following:

``Verdi — Verdi Reverse Interactive Debug exemplifies the power of VCS engines and technologies natively
integrated in the Verdi debug environment, and vice versa (Figure 9).

Reverse debug
control

Full interactive
control

Figure 9. Verdi/VCS Reverse Interactive Debug—go back in time without setting checkpoints

``Static and Formal – VC LP and VC Formal both fully support Unified Compile with VCS and Unified Debug
with Verdi

``Emulation – VCS congruent mode enables simulation to match actual hardware and facilitates emulation-
simulation interoperability

``VIP – Synopsys’ VC Verification IP solution offers native integration with VCS’ planning, coverage and
constraint solver technologies, and provides native Verdi-based debug and Protocol Analyzer capabilities

Conclusion

With VCS, not only does one get the industry leading performance and capacity in simulation, but also the
fully integrated suite of technologies and tools built around the simulator to drive any verification strategy a
designer wants to execute. The product roadmap for VCS technologies and verification flow in general follows
the path treaded by the design leaders in the industry. In addition, VCS comes with the top-notch support so
that verification schedules stay on track.

6

For more information about Synopsys products, support services or training, visit us on the web at:
www.synopsys.com, contact your local sales representative or call 650.584.5000.

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05/17/16.AL_CS7167_VCS_DS.